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In 1540, in Ingolstadt, Germany, the influential astronomer and printer Peter Apian produced the Astronomicum Caesareum: a printed and hand-coloured astronomical book visualising the Ptolemaic universe through the use of diagrams and wheelcharts, worthy of his imperial patron, Charles V. About 130 copies have survived to this day, with varying degrees of paper quality and level of decoration, and only eleven volumes are considered deluxe copies. We thoroughly analysed one deluxe volume held at the Fitzwilliam Museum, Cambridge, and compared the results with four (one deluxe and three standard) other copies from institutions in the UK. A non-invasive analytical protocol was applied, including extensive microscopy, fibre-optic reflectance spectroscopy (FORS), X-ray spectroscopy (XRF), macroscale XRF (MA-XRF) and Raman spectroscopy. The most interesting pages were chosen based on art-historical evidence and the variety of the colour palette, including on volvelles (wheelcharts) and coats of arms. Following a systematic approach, we analysed the same pages in each volume, gathering information on the colour palette in all the volumes. The type of paper and the presence of watermarks were also documented. A wide range of materials was identified in the five copies, including red, purple and yellow organic dyes, lead white, verdigris, vermilion, azurite, indigo, smalt, and lead–tin yellow. Mosaic gold was used to embellish certain paint passages in the deluxe volumes and metals (gold and silver) were applied on some pages. The comprehensive findings were essential to identify specific traits related to Apian's workshop, to differentiate deluxe from standard copies, to suggest an order of production of the copies, and to provide new information on this landmark book and more generally in an under-researched field of study. [ABSTRACT FROM AUTHOR]

In this paper, three-dimensional TiO2 nanoflowers (NFs) were prepared by a facile hydrothermal method, and Ag3PO4 was grown in situ following alkali treatment to design and synthesize a Ag3PO4/OH/TiO2 catalyst with excellent photocatalytic activity under visible light. The test results show that the photocatalytic degradation performance of TiO2 NFs after alkali treatment and Ag3PO4 loading is significantly improved. This is because the alkali treatment and the introduction of Ag3PO4 can provide a large amount of –OH, which can be converted to ˙OH under UV irradiation, followed by an increase in the number of active radicals to enhance the photocatalytic degradation performance. Meanwhile, the introduction of Ag3PO4 can effectively improve the light absorption ability of the photocatalyst. Moreover, the in situ growth of Ag3PO4 on TiO2 NFs can construct a high-quality Ag3PO4/TiO2 heterojunction to promote the charge separation and transport. Therefore, the degradation rate of Ag3PO4/OH/TiO2 can reach 90% after 30 min for degrading 3 mg L−1 RhB under visible light. The Ag3PO4/OH/TiO2 photocatalyst designed in the present work provides a new tool for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Wood specimens were dyed by boiling them in the presence of walnut shells and dye to penetrate the dyestuff into the sample. Specimens prepared from Scots pine, oak, and beech woods were boiled separately in walnut shell, water, and NaOH environment, and the penetration of the dyestuff into the samples was ensured. Sodium hydroxide solution was preferred because it facilitates the dissolution of the hemicelluloses in the wood and the dyestuffs in the walnut shell. Alum was added in other samples to reveal the mordant effect on the adhesion of dyestuffs to wood. Thermogravimetric (TG) analysis revealed that wood degradation primarily occurs due to evaporation of free water at 50 to 120 ℃, followed by lignin and cellulose breakdown across a wide temperature range of 160 to 600 ℃. Treatment with NaOH and NaOH+alum notably reduced the peak temperatures in differential-thermogravimetric analysis by indicating an effect on lignin. This was supported by Fourier transform infrared analysis, particularly in the disappearance of carboxyl groups at 1710 cm-1 and significant decreases in peak intensities at 1027, 1247, 1315, and 1501 cm-1. Based on the findings, it was concluded that the dyed parts obtained can be used in the wooden toy industry. [ABSTRACT FROM AUTHOR]

Magnetic separation of photocatalysts holds great promise for water treatment. A magnetic separation method has a positive effect on the recovery of catalysts after degradation. In this paper, an efficient and reusable catalytic system is developed based on coating magnetic Fe3O4 by depositing Fe2+ on the surface of ZnO. The Fe3O4/ZnO nanocomposite exhibits enhanced performance for organic pollutant degradation. The Fe3O4/ZnO system demonstrates a high photocatalytic activity of 100% degradation efficiency in Rhodamine B (RhB) degradation under UV light irradiation for 50 min. The excellent photocatalytic activity is primarily due to the separation of photogenerated electron-hole pairs being facilitated by the strong interaction between Fe3O4 and ZnO. The induction of the magnetic Fe3O4 endows the Fe3O4/ZnO composite with superior magnetic separation capability from water. Experiments with different radical scavengers revealed that the hydroxyl radical (·OH) is the key reactive radical for the effective degradation of RhB. This work innovatively affords a common interfacial dopant deposition strategy for catalytic application in the degradation of organic dye pollutants and catalyst separation from wastewater efficiently. [ABSTRACT FROM AUTHOR]

This study focuses on the synthesis of BaPbFe2O6 and modifying its photocatalytic activity by precipitation method on brilliant green (BG) dye. According to the characterization data, the UV-Vis absorption spectrum shows several peaks with an optical band gap of 5.45 eV. FESEM images showed irregular shapes of BaPbFe2O6 and EDX confirmed the presence of, Ba, Pb, Fe and O elements. The average particle size measured with maximum diffraction peak using Scherrer's equation was 12.31nm. XPS represents the different oxidation states of the elements. FTIR images show the presence of oxide film on the surface with a band gap of 500-600 cm-1 given as the characteristic stretched band of Pb-O. Maximum degradation is shown on the above optimum condition and complete degradation was held in 20 min on optimum conditions. The degradation rate of BaPbFe2O6 is 86.89% of 4*10-5 M for BG dye by exposing to sunlight for 20 minutes. Degradation of BG dye occurs due to the formation of hydroxyl radicals (.OH) on exposure to sunlight following pseudo first order kinetics. Therefore, BaPbFe2O6 synthesized in this paper can be used for the degradation of other exogenous organisms and for the treatment of wastewater and environmental polluted samples. [ABSTRACT FROM AUTHOR]

The combined application of Cathodoluminescence (CL) with Scanning Electron Microscopy (SEM) on paintings and painted surfaces has the potential to identify both organic and inorganic pigments on a micrometre or even nanometre scale. Additionally, the combination with Energy-Dispersive Spectrometry (EDS) allows for a more holistic, elemental, and mineralogical characterization of pigments. In addressing the need for the creation of a robust, open access database of characteristic CL spectra of pigments, a large project has been undertaken, focusing primarily on common organic and inorganic pigments. The present paper focuses on the CL characterization of 10 significant blue pigments in pure powder form: cerulean blue, Egyptian blue, Han blue, indigo, lapis lazuli, Maya blue, phthalo blue, vivianite, ultramarine blue, and zirconium blue. The CL spectra present characteristic bands for most of the pigments, allowing their secure identification, especially when combining the results with the EDS analyses. The effect of binding media and of the mixture of different pigments was also studied, via the analysis of mixtures of pigments with oil painted over canvas. Overall, both the binding medium and the mixture of pigments do not appear to create significant differences in the occurring spectra, thus allowing the identification of individual pigments. EDS and RAMAN spectra are included in order to facilitate comparison with other databases. [ABSTRACT FROM AUTHOR]

In this paper, coal gangue, a solid waste is used as raw material to provide silicon and aluminum sources for synthesis of zeolite. A coal gangue zeolite based Cu/Fe–X catalyst is successfully prepared by immersion-calcination method, which is used to remove Rhodamine B from aqueous solution. The characterization results show that Cu and Fe have been successfully loaded on zeolite, not damaged its structure, and these nanoparticles are highly dispersed and low crystallinity. This special structure will enhance its catalytic ability to activate H2O2. The experiment showed that hydroxyl radical (·OH) was the main active species for catalytic degradation of Rhodamine B, and the circulation of Cu2+ to Cu1+ and Fe3+ to Fe2+ could synergistically produce ·OH. Furthermore, the redox potential of Cu1+ and Cu2+ is lower than Fe2+ and Fe3+, which can promote Fe3+ circulate to Fe2+, further promote Fe2+ to activate H2O2 to decompose into ·OH, and overcome the speed limiting step of Fenton-Like catalytic reaction. The Cu/Fe–X catalyst can activate H2O2 in wide pH range (1–10). Under optimal conditions, the catalytic degradation rate can reach 99.9%, and the TOC removal rate is as high as 98.5%. Therefore, Cu/Fe–X/H2O2 system can effectively remove organic dyes, and has a high industrial application prospect. [ABSTRACT FROM AUTHOR]

This paper studies the composition and properties of shells of bivalve mollusks (Crenomytilus grayanus, Callista brevisiphonata, and Mizuhopecten yessoensis) from coastal discharges with a view to the possibility of their use in photocatalytic water treatment systems. The clam shells are considered in terms of application in the form of a powder material as a precursor for creating photocatalysts, and also as a carrier of photocatalytic coatings. It was shown that the main phase composing the shell material was calcium carbonate in two crystallographic modifications—calcite and aragonite. The presence of inorganic impurities in all studied clam shells did not exceed one mass percent. The main share was made up of elements included in the composition of calcium carbonate, which confirmed the high bio-indifference of the materials under study. Depending on the physiological and environmental features of the structure of clam shells, different contents of the organic component in their composition were observed. The granulometric characteristics of crushed clam shells (average diameter, specific surface area, and distribution modality) were studied. It was shown that the maximum values of bending strength of 5 MPa and compressive strength of 2 MPa are characterized by Mizuhopecten yessoensis shells with the lowest porosity of 2.91%. The features of sorption and photosorption processes of both whole and crushed shells in relation to four organic dyes at different temperatures and degrees of illumination were studied. Based on crushed shells of Mizuhopecten Yessoensis and titanium dioxide, functional materials (CaxTiyOz) were obtained, and their morphology and photocatalytic properties were studied. An example of the practical use of clam shells as a carrier of a photocatalytic coating is given. [ABSTRACT FROM AUTHOR]

The interaction of decavanadate with the cationic organic dyes methylene blue (MB), toluidine blue (TB) and rhodamine B (RB) was explored. For that purpose, a novel decavanadate salt (2,3-ampH)6[V10O28]·4H2O (2,3-ampV10), where 2,3-ampH+ = 2-amino-3-methylpyridinium, and two salts with the organic dyes (MB)4[H2V10O28]·10.8H2O (MBV10) and (TB)4(H2V10O28)·10H2O (TBV10) were synthesized. The compounds were characterized by elemental analysis, powder X-ray diffraction, energy dispersive X-ray spectroscopy, scanning electron microscopy and infrared spectroscopy. The salts 2,3-ampV10 and MBV10 were also characterized by single-crystal X-ray diffraction, while TBV10 was isolated as an amorphous solid. The supramolecular features of MBV10 showed columns of MB cations connected to V10 through H-bond interactions that resulted in channels filled with water molecules. The absorption spectrum of MBV10 was studied by density functional theory (DFT) calculations at the X3LYP/def2-TZVP level using the crystallographic data. The efficacy of 2,3-ampV10 to bleach MB solutions at pH 6.2–6.5 was outstanding, achieving nearly 90% discoloration in only 5 min, presenting moderate efficacy towards TB and quite negligible towards RB. Moreover, a metachromatic effect was observed in the TB solution at pH 3. The IR spectra of the isolated solids and the mass spectra of the supernatants suggest both adsorption and cation exchange as the main responsible processes for the bleaching of MB and TB solutions. The present work has tackled many fronts related to the chemistry of POVs, mainly synthetic, structural, and environmental approaches. [ABSTRACT FROM AUTHOR]

We have selected a semi-rigid hexacarboxylic acid ligand H6L enriched with oxygen-active sites with Cd2+ salt, successfully synthesising a 3-D anionic material MOF-1 ([(CH3)2NH2]2[Cd2L]·3DMA·2H2O, H6L = 5,5',5"-(benzene-1,3,5-triyltris(oxy))triisophthalic acid). The structure of this carboxylic acid ligand is triangular in shape, which contributes to the formation of the 3-D framework structure, and its semi-rigidity facilitates entry of dye molecules by slightly adjusting the pore size. The larger pore size of MOF-1 is 1.45 nm x 0.86 nm. The oxygen spacer groups are uniformly distributed throughout the framework, promoting the adsorption of MOF-1 for dyes. Based on these factors, there is a significant advantage in that the anionic material MOF-1 containing [(CH3)2NH2]+ selectively adsorbs cationic organic dyes from aqueous contaminants for recycling. It was discovered that the adsorption process' equilibrium and kinetics followed the Langmuir isothermal model and pseudo-secondary kinetics, respectively. And we measured the adsorption rate of MOF-1' on MB+ to be 1.77 x 10-3 g mg-1 min-1. Its relatively high capacity is ca. 1220 mg g-1. After five cycles of adsorption and desorption, the dye adsorption performance was reduced to ca. 80% and the framework stability remained well. [ABSTRACT FROM AUTHOR]

A caged metal–organic framework based on heptanuclear and binuclear copper clusters, namely [Cu9(L)10(H2O)2][Me2NH2+]2 (Cu-MOF) (L = rigid 6-(1H-tetrazol-5-yl)-2-naphthoic acid) was synthesized and structurally characterized by a solvothermal method. Single-crystal X-ray diffraction shows that Cu-MOF displays a three-dimensional porous anionic framework and exhibits a cage-cavity structure. The tri-functional ligand uses two coordination modes to bridge different SBUs to form a dodecahedral cage. Since Cu-MOF possesses both anionic and porous frameworks, it could be used for efficient and selective absorption of cationic organic dyes. Further studies truly showed that both the charge and size of the dye molecules affect the absorption of Cu-MOF. Besides, thanks to the electronic configuration and wide range of visible light absorption properties of the heptanuclear copper clusters, Cu-MOF could be used as a photocatalyst for energy transfer from oxygen molecules to singlet oxygen, and successfully oxidized benzyl alcohol to benzoic acid in air under additive-free mild conditions. Therefore, rationally prepared Cu-MOFs, guided by crystal engineering, demonstrate potential for application as organic dye adsorption separators and photocatalysts, and the feasibility of preparing functionally tailored frameworks using tri-functional ligands consisting of tetrazolium and carboxylate acid is presented. [ABSTRACT FROM AUTHOR]

Multinuclear (di/tri) copper(II) complexes bridged through hydroxyl groups are very interesting coordination complexes owing to their potential applications in various fields. In this work, three novel dinuclear (μ-hydroxo)-bridged copper(II) complexes in the crystal form, namely, [Cu2(3,5-DIFLB)2(H2tea)2](H2O) (1), [Cu2(4-ClB)2(H2tea)2](H2O) (2), and [Cu2(4-ETHB)2(H2tea)2](H2O)2 (3) (where DIFLB = difluorobenzoate, CLB = chlorobenzoate, ETHB = ethoxybenzoate, and H3tea = triethanolamine), were isolated at room temperature using methanol and water in a 4 : 1 v/v ratio as a solvent. Furthermore, all three complexes (1–3) were characterised using spectroscopic (UV-vis, DRS, and FT-IR), electrochemical (CV) and single-crystal X-ray diffraction techniques. Structural insights gained by packing analysis revealed the role of steric constraints of substituents and various non-covalent interactions in lattice stabilization, which were indeed supported by theoretical and molecular electrostatic potential illustrations. Hirshfeld surface analysis provided quantitative verification about various non-covalent interactions (interatomic contacts) involved in the packing of molecules. Interestingly, as a potential application, complexes 1–3 all exhibited remarkable visible light-mediated photo-Fenton degradation of approximately 98% for 50 ppm concentration of organic dyes (fuchsin basic (FB) and methyl orange (MO)) in 90 minutes with the optimized conditions of 1 mg mL−1 of dye solution. In all the cases, dye degradation by these materials was ascribed to the symbiotic relations among the molecular structures of complexes 1–3, which were endowed with various electron-withdrawing and electron-releasing substituents and ionic strength, with respect to the structure, shape and interacting patterns of dye molecules. The adsorption mechanism indicates that various weak interactions between the donor and acceptor groups of complexes and dyes, such as electrostatic, hydrogen bonding, and direct coordination to metal sites, play a crucial role, which is confirmed by molecular dynamics (MD) simulations. Theoretical studies by DFT-based descriptors, molecular electrostatic potentials, and band gaps provided deep insights into various electronic and reactivity parameters. For subsequent processes of dye degradation, complexes 1–3 were stable and recoverable. The successful integration of experimental and theoretical approaches sheds light on copper-based dinuclear stable coordination complexes, showcasing a significant step towards the development of novel heterogeneous photo-Fenton catalysts. [ABSTRACT FROM AUTHOR]

In this research, Sr-doped hydroxyapatite, HAp and NiO nanoparticles were used to produce a novel nanocomposite, Sr-doped HAp/NiO. Various analytical and instrumentation techniques such as FTIR, PXRD, UV-DRS, SEM, TEM, and XPS were used to characterize the as synthesized composite material. The nanocomposite acts as an efficient photocatalyst and is able to degrade Congo red (CR) dye up to 95.6% within 40 min under solar light irradiation without any kind of external additive. The HR LC–MS spectrum was recorded to determine the degradation products of the chosen organic dye. Furthermore, the as prepared nanocatalyst also effectively reduced 98.7% of carcinogenic Cr(VI) to Cr(III) within just 10 min. In order to propose the photocatalytic mechanism and to detect the active radicals present, a radical trapping experiment was conducted. As an appealing photocatalyst for wastewater treatment and reduction of toxic chemicals, the research concluded with a methodical and cost-effective process for producing the Sr-doped HAp/NiO nanocomposite. [ABSTRACT FROM AUTHOR]

Photo-Fenton catalysis plays an important role in the degradation of organic pollutants in environmental sewage. In this paper, magnetic 0D/1D ZnFe2O4/ZnCO3 rod-like nanocomposites were fabricated by a simple one-pot solvothermal method, and then the produced magnetic 0D/1D ZnFe2O4/ZnO rod-like nanocomposites were formed via calcination at high temperature. The obtained 0D/1D ZnFe2O4/ZnCO3 has been fully investigated by x-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, x-ray photoelectron spectroscopy, and vibrating sample magnetometry. Furthermore, the photocatalytic Fenton reaction of these two catalysts has been preliminarily evaluated for the degradation performance of organic dyes and antibiotics in wastewater. The results showed that, under visible-light irradiation, the ZnFe2O4/ZnCO3 composite material and its product, ZnFe2O4/ZnO, after high-temperature firing can achieve more than 90% photo-Fenton catalytic degradation of Rhodamine B (RhB) and tetracycline (TC) within 30 min, superior to that of ZnFe2O4, ZnCO3 , and ZnO monomers due to their larger specific surface area and more active sites. The magnetization saturation values of ZnFe2O4/ZnCO3-2 and ZnFe2O4/ZnO-2 were, respectively, around 34.20 emu/g and 15.00 emu/g, indicating that both have good magnetic recovery properties. After five cycles of experiments, the photo-Fenton catalytic properties of ZnFe2O4/ZnCO3-2 and ZnFe2O4/ZnO-2 on TC decreased slightly within 30 min, but the Fenton catalytic properties of RhB still maintained more than 98%, indicating that both have good magnetic recovery properties and strong structural stability. A possible photo-Fenton catalytic mechanism has been proposed based on free radical identification, electrochemical impedance spectra, photocurrent curves, and a Mott–Schottky diagram. This study provided two catalysts with excellent performance for the photo-Fenton catalytic degradation of pollutants in water. [ABSTRACT FROM AUTHOR]

Developing economical and high‐performing sensitizers is crucial in advancing dye‐sensitized solar cells (DSSCs) and optoelectronics. This research paper explores the potential of novel red light‐absorbing organic dyes based on Indolo[3,2‐b]carbazole (ICZ) as the donor applied in co‐sensitizer‐free DSSCs for breakthroughs in photovoltaic (PV) applications. DFT and TD‐DFT based computational methods were employed to calculate the conduction band levels, electron injection capabilities, and power conversion efficiency (PCE) of metal‐free organic dyes (ICZ1–ICZ9) having D‐A‐π‐A architecture. Comprehensive analyses included NBO, DOS, FMO, ICT, MEP, binding energy, and TDM analysis. Quantum chemical calculations of the structural, photochemical, and electrochemical properties, as well as the key parameters, reveals that all the designed dyes could be an excellent candidate for high‐efficiency DSSCs due the small energy gap (2.130–1.947 eV), longer wavelength absorption (759.47–520.63 nm), longer lifetimes (15.65–6.67 ns), a lower ΔGreg (0.29–0.14 eV), a significant dipole moment changes (31.489–16.195D), LHE (0.95‐0.46), the large qCT (0.962–0.689), small DCT (7.657, 4.897 Å), and VOC (1.13–0.86 eV). This quantum simulation showed that, when compared to reference D8, the photovoltaic dyes ICZ8, ICZ2, and ICZ7 are recognized as being eye‐catching. Furthermore, dye@(TiO2)9 cluster model results demonstrate promising prospects for enhancing the photovoltaic (PV) performance of ICZ1–ICZ9 dyes by electron injection and conduction band (CB) engineering. This study will help the experimentalists for developing ICZ‐based PVs as more efficient and sustainable energy solutions. [ABSTRACT FROM AUTHOR]

Mesoporous titania films with worm-like patterns were fabricated on indium-tin oxide (ITO) glass by dip-coating skill, and were characterized systematically. Impacts of the process and technical parameters on the formation of the films were investigated. The mesoporous films were characterized by low-angle X-ray diffraction (XRD) and wide-angle XRD, transmission electron microscopy (TEM), scanning electron microscope (SEM), linear sweep voltammograms and nitrogen adsorption/desorption isotherms. Subsequently, the films were used in a photoelectrocatalytic system for the degradation of methyl orange. The influence of operation variables, including pH values, bias potential, light intensity, organics concentration and the mass of the films, on the degradation of the dye was investigated in details. More than 96 % degradation of the organics was achieved in 2 h. The kinetic results for the photoelectrocatalytic oxidation of the organic were also presented in this paper. [ABSTRACT FROM AUTHOR]

In this paper, undoped and copper-doped ZnO nanoparticles (NPs) were successfully synthesized using a gliding arc discharge (GAD) plasma technique, which is a sustainable, cost-effective, and scalable method. This method offers several advantages over traditional synthesis methods. The synthesized NPs were characterized by various techniques to understand their physicochemical properties. XRD analysis confirmed the presence of characteristic peaks of pure ZnO, while doped samples exhibited additional peaks corresponding to CuO crystal planes, indicating the successful incorporation of Cu into the lattice. As obvious, bare ZnO showed absorption peak at 378 nm corresponding to the band gap of 3.21 eV. The band gap of Cu-doped samples increased systematically, i.e., 3.35 eV for 2% Cu, 3.47 eV for 4% Cu, and 3.66 eV for 6% Cu. SEM images revealed aggregation and increase in particle size with the increasing in Cu concentration. EDAX analysis revealed a decrease in the weight percentage of oxygen and zinc with the increase in Cu concentration, suggesting structural changes within the lattice. Furthermore, the antibacterial activity against Gram-positive and Gram-negative bacteria, antioxidant activity, and photocatalytic activity against three different organic dyes such as Brilliant Cresyl Blue (BCB), Methylene Blue (MB), and Congo Red (CR) was studied. It is found that the photocatalytic activity of ZnO NPs varies with Cu concentration, leading to a decrease in its performance. The antibacterial activity of the NPs was also assessed, with undoped ZnO NPs showing dose-dependent effects against bacteria, while the Cu-doped ZnO NPs exhibited decreased efficacy. Interestingly, Cu doping significantly enhanced the antioxidant activity of the NPs compared to the undoped ZnO. [ABSTRACT FROM AUTHOR]

In response to growing concerns regarding the environmental impact of traditional chemical synthesis methods, this study delves into the phytoconstituents-based green synthesis of copper oxide (CuO) nanoparticles (NPs) as a promising alternative. The study aimed to synthesize CuO NPs using eco-friendly methods with Erythrina variegata and then explore their anticancer, antibacterial, and photocatalytic properties. CuO NPs' structural and optical properties were comprehensively analyzed using UV-vis, XRD, FTIR, XPS, DLS, SEM, and HRTEM, with elemental mapping performed via EDAX. Cytotoxicity assays were conducted on cervical cancer HeLa cells and HEK293 noncancerous cells. The band gap of the CuO NPs was determined to be 3.781 eV, with a crystal size of 17.15 nm and a zeta potential of −23.1 mV. Remarkably, the synthesized nanoparticles exhibited a spherical morphology and demonstrated significant cytotoxicity against HeLa cells with an IC50 value of 48 ± 5 μg mL−1 while displaying lower toxicity towards HEK293 cells. Additionally, the prepared CuO NPs demonstrated dose-dependent anticancer potential, inhibiting cell migration and colony formation, and inducing apoptosis in HeLa cells. Moreover, the antibacterial activity of the prepared CuO NPs against S. aureus and E. coli paralleled that of the standard antibiotic streptomycin. Furthermore, we evaluated the photocatalytic capability of the developed CuO NPs, which demonstrated significant photocatalytic activity with a 91.12% degradation of the organic dye methylene blue in 180 min under UV irradiation, demonstrating their potential for breaking down organic pollutants in the environment. This study emphasizes the eco-friendly synthesis of CuO NPs, promising significant impacts on energy, the environment, and medicine through sustainable approaches. [ABSTRACT FROM AUTHOR]

Comprehensive strategies with the development of advanced materials are required for the remediation of water and land pollution to protect the environment and human health. In this regard, iron oxide catalysts are recognized as preferable catalysts for the heterogeneous photo-Fenton process, which is an efficient technique for degrading organic pollutants in waste water. The present study discusses the photocatalytic performance of iron oxide-based catalysts synthesized from industrial waste red mud for methylene blue degradation under visible light irradiation. XRD studies confirmed the formation of a pure α-Fe2O3 (hematite) phase, whereas the doping of iron oxide with Mn, Cu, and Ce was ascertained by XPS analysis. 3 wt% Cu doped iron oxide with a TOC value of ∼84.7% showed the best removal efficacy to the tune of ∼91% within 60 min of visible light irradiation. Impedance data supports the enhanced charge separation in metal doped α-Fe2O3, which improves the photocatalytic performance. A similar trend was observed in photo-electrochemical (PEC) properties, where Cu doped Fe2O3 showed 2 times higher photocurrent than the bare one. Based on scavenging tests, electrons and hydroxyl radicals (˙OH) were shown to be major players in the photodegradation of pollutants under visible light. A probable mechanism explaining the enhanced e−/h+ pair separation and migration was proposed by examining electrochemical properties. This work has significant implications for wastewater treatment with the efficient use of industrial waste red mud as a cost-effective resource. [ABSTRACT FROM AUTHOR]

Pigments play a pivotal role in the cosmetic industry, in which the development of pigments with concurrent color diversity, hydrophobicity, biocompatibility and photostability remains a great challenge. Herein, we report organic–inorganic composite pigments synthesized via a combination of organic dye anions (Ponceau SX and acid green (AG)), layered double hydroxides (LDHs) and octyltriethoxysilane (OTEOS) (denoted as O/Dye-LDHs: O/SX-LDHs and O/AG-LDHs).The prepared composite pigments were characterized via a comprehensive investigation based on X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS-mapping), Fourier transform infrared (FT-IR) spectroscopy, CIE 1976 L*a*b* color scales, static contact angle measurement and HET-CAM assay. The results confirm the successful intercalation of organic dye anions into the interlayer region of LDHs via host–guest interactions and the surface modification of OTEOS on the layer surface, forming a new kind of hydrophobic organic–inorganic composite pigment with a sandwich structure. LDH layer protection and OTEOS coating play crucial roles in the high photostability, good hydrophobicity and satisfactory biocompatibility of pigments. In addition, O/Dye-LDHs exhibit rich color and color adjustability. Impressively, we applied mixture composite pigments with different O/SX-LDH-to-O/AG-LDH ratios to formulate an eye shadow cream, which present a series of popular and natural colours with water resistance to enhance one's attractiveness and appearance. This work provides a promising strategy for the design of safe and efficient composite pigments, demonstrating their potential application in the field of makeup. [ABSTRACT FROM AUTHOR]

Rapid industrialization and ever-growing human activities have caused more and more serious water pollution in the last few decades, posing great threats towards both human health and ecological environment. Organic dyes, as one of the major water pollutants, are usually toxic, chemically stable, and hard to degrade. In this paper, a novel PCN-222(Zn)/GO composite was obtained by combining porphyrin-based metal organic framework material PCN-222(Zn) with graphene oxide (GO). The structure and morphology of the composite were characterized by FTIR, XRD, SEM, and optical microscopy. The thermal stability and optical properties were studied by thermogravimetric analysis (TGA) and fluorescence spectroscopy. PCN-222(Zn) and PCN-222(Zn)/GO were used as both adsorbents and photocatalysts for the adsorption and visible light photodegradation of organic dye methylene blue in aqueous solutions. It is found that the blending of GO can improve the photocatalytic degradation activity of PCN-222(Zn) towards organic dyes. [ABSTRACT FROM AUTHOR]

Water pollutants of non-biodegradable toxic aromatic dye including Methylene blue (MB) and Rhodamine (RhB) are extremely carcinogenic thiazines used in various industries such as leather industry, paper industry, and the dyeing industry. The presence of dyes in wastewater causes severe threats to human health that are responsible for various harmful chronic or acute diseases and also shows an adverse impact on the environment as it reduces transparency and is harmful to water microorganisms. To overcome severe issues, many traditional techniques have been used to remove toxic pollutants, but these methods are insufficient to remove chemically stable dyes that remain in the treated wastewater. However, the photocatalytic degradation process is an efficient approach to degrade the dye up to the maximum extent with improved efficiency. Therefore, in this work, a new class of two-dimensional (2D) transition metal carbide of Titanium Carbide (Ti3C2Tx) MXene material was used for the organic dyes degradation such as MB and RhB using a photocatalytic process. A layered structure of hexagonal lattice symmetry of Ti3C2Tx MXene was successfully synthesized from the Titanium Aluminum Carbide of Ti3AlC2 bulk phase using an exfoliation process. Further, the XRD spectrum confirms the transformation of bulk MAX phase having (002) plane at 9.2° to Ti3C2Tx MXene of (002) plane at 8.88° confirms the successful removal of Al layer from MAX phase. A smooth, transparent, thin sheet-like morphology of Ti3C2Tx nanosheet size were found to be in the range of 70 to 150 nm evaluated from TEM images. Also, no holes or damages in the thin sheets were found after the treatment with strong hydrofluoric acid confirms the formation Ti3C2Tx layered sheets. The synthesized Ti3C2Tx MXene possesses excellent photocatalytic activity for the degradation of dyes MB, RhB, and mixtures of MB and RhB dyes. MB dye degraded with a degradation percentage efficiency of 99.32% in 30 min, while RhB dye was degraded upto 98.9% in 30 min. Also, experiments were conducted for degradation of mixture of MB and RhB dyes by UV light, and the degradation percentage efficiency were found to be 98.9% and 99.75% for mixture of MB and RhB dye in 45 min, respectively. Moreover, reaction rate constant (k) was determined for each dye of MB, RhB, and mixtures of MB and RhB and was found to be 0.0215 min−1 and 0.0058 min−1, and for mixtures, it was 0.0020 min−1 and 0.009 min−1, respectively. [ABSTRACT FROM AUTHOR]

It is necessary to develop methods for rapid degradation of untreated waterborne contaminants due to their serious impact on the environment and human health. Here, we proposed a rapid and efficient microplasma electrochemistry (MIPEC) method for organic dye and antibiotic degradation. The atmospheric-pressure plasma acted as the anode and it could generate reactive radicals for rapid and complete degradation of rhodamine B (RhB) in about 6 min, which is one of the fastest methods to our knowledge. Similarly, the degradation of ciprofloxacin (CIP) has also been achieved. This method with mild and convenient operation conditions could be applied in a wide pH range due to the unique properties of the plasma anode, unrestricted by the pH of wastewater. The mechanism study revealed that more reactive species could be generated at the plasma anode than at the cathode, leading to a faster reaction rate at the anode side and the presence of oxygen could also accelerate the generation of reactive species. Besides, the MIPEC method can be used to treat a variety of dyes separately and together in minutes in different water bodies, making it a universal method suitable for treating different dyes in wastewater. This work provides a rapid and efficient method for waterborne contaminant degradation without any secondary pollution and need for post treatment, and also broadens the application field of the MIPEC method. [ABSTRACT FROM AUTHOR]

The results of evaluating the adsorption and fluorescent properties of azolotriazine compounds and phases based on cadmium sulfide quantum dots in vapors of volatile organic compounds (biomarkers of living systems) are considered. The adsorption properties of phases based on organic dyes and encapsulated semiconductors towards vapors of alcohols, ketones, amines, acids, ammonia, and aldehydes are investigated using direct high-sensitivity piezoelectric quartz microweighing. The spectral properties and their variations in analyte vapors are investigated using various spectroscopy methods (absorption, photoluminescence). The research results are compared, and the potential for optimizing this stage is assessed. It is proposed to evaluate the consistency of methods for predicting changes in fluorescent properties in test systems for volatile organic compounds using the Kendall coefficient of concordance, W. The highest level of agreement (W = 0.89) was observed between the methods of spectrofluorimetry and direct vapor microweighing upon adsorption on phases being potential fillers of test systems. A correlation between the results obtained by different fluorescence methods (visual plate test systems and fluorimetry of phases on paper substrates) is 0.80, which confirms a high degree of consistency in assessments using them in the degree of interaction between the analytes and organic, combined fluorochromes. The methods closely related in the nature of the analytical response do not exhibit better agreement than the method of direct vapor microweighing on microphases of fluorimetric reagents of different nature (cadmium sulfide quantum dots/chitosan, organic azolotriazine compounds, mixed phases). This, in turn, enables the selection of simpler, more available, and more rapid methods and means of analysis in routine experiments. [ABSTRACT FROM AUTHOR]

Water, essential for all life, faces contamination challenges due to industrialization and unchecked urban development, producing pollutants such as organic dyes, detergents, heavy metals, and pesticides. This has emerged as one of the most pressing environmental concerns in recent years, with a particular emphasis on organic dyes due to their demonstrated health-related concerns. In this context, this paper reviews the use of photocatalysis as a wastewater treatment method, highlighting its significant potential for removing organic dyes from aqueous solutions. Additionally, the focus is on the design, development, performance enhancement, and overall research progress in fabricating graphene-based semiconductor nanocomposites as photocatalysts. Representative examples are discussed, emphasizing the potential of these nanocomposites in degrading toxic organic dyes through photocatalysis. The enhanced photoactivity is attributed to the synergistic effects of graphene and semiconductor materials, leading to improved light absorption, charge separation, and reactive oxygen species generation. This comprehensive review provides valuable insights to advance wastewater treatment technologies and address environmental impacts caused by organic dye pollution. [ABSTRACT FROM AUTHOR]

Subphthalocyanines (SubPcs) have emerged as promising organic dyes for the development of efficient artificial photosynthetic devices, offering intense absorption in the visible region along with excellent charge transport properties. In this study, four novel SubPc derivatives containing carboxylic acid and various peripheral substituents were synthesized as a panchromatic photosensitizer to prepare an efficient and stable TiO2-based photocatalytic system for co-catalyst-free photocatalytic hydrogen evolution. To compare the influence of the nature of the peripheral substituents on photocatalytic activity, SubPc derivatives (coded as SubPc 1–4) were decorated with substituents having different electron-donating capabilities, such as alkyl thio, benzodioxin, amine, and iodo units, respectively. Photocatalytic activities were examined in the presence of TEOA as a sacrificial agent under irradiation with λ > 400 nm without co-catalyst loading. SubPc 1/TiO2 shows the best photocatalytic activity among the SubPc-sensitized photocatalysts, with a hydrogen evolution rate of 0.176 mmol h−1. While the activity of all four SubPc-based photocatalysts increased significantly after 24 h irradiation, notably, SubPc 1/TiO2 exhibited remarkable catalytic activity, achieving a hydrogen evolution rate of 6.017 mmol with a high turnover number (TON) value of 12 279 for hydrogen production. This study highlights the potential of SubPc-based sensitizers for co-catalyst-free photocatalytic H2 production and offers valuable insights into the impact of peripheral units in SubPc/TiO2-based photocatalytic systems. [ABSTRACT FROM AUTHOR]

A novel ethylene-bridged silsesquioxane was synthesized by a heat-induced thiol–ene addition reaction of 2-acetylthioethanethiol to 1,2-bis(triethoxysilyl)ethene. Upon deacetylation, the formed organosiloxane precursor bearing the dithiol moiety (–SCH2CH2SH) self-assembled into a sulfur-rich PMO material in the presence of the structure-directing agent under acidic conditions. The loading of sulfur-bound ligands in the PMO framework can be adjusted by co-condensing the precursor with tetraethyl orthosilicate. The structure of the resulting PMOs was characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, infrared spectroscopy, and nitrogen adsorption and desorption studies. The PMO prepared by using the thio-bis-silane precursor alone can be used for efficient and fast capture of mercury ions from water with a saturation Hg(II) uptake capacity of 1253 mg g−1 and recycled several times with negligible loss in the adsorption efficiency. This material also showed a high adsorption selectivity for Hg(II) over other competitive metal ions like Zn2+, Pb2+, Fe3+, Cu2+ and Mn2+. Remarkably, the new adsorbent proved to be effective for simultaneously removing Hg(II) and rhodamine B (RhB) from simulated sewage with removal rates of over 97% and 91% for both at 100 ppm, respectively, indicating its potential for the practical application in environmental remediation. [ABSTRACT FROM AUTHOR]

Works of art, especially paintings, often involve successive layers of materials of diverse compositions and properties. The current study explores the potentialities of the combination of femtosecond Laser Induced Breakdown Spectroscopy (fs-LIBS) and Macro X-ray Fluorescence (MA-XRF) for the study of paintings. In this framework, two mock-up samples that were manufactured by using traditional post-byzantine painting methods and numerous inorganic and organic pigments was thoroughly investigated. The selected pigments were either applied as single paint layers on top of a calcium carbonate substrate or as a combination of two and/or three successive paint layers over the substrate. The authors attempt to disclose the layered structure of the paints by inspecting some carefully chosen LIBS spectral features (markers) as a function of the laser shot number. The various paint layers are identified by applying less than ten laser shots while the diameter of the induced craters is limited to under 100 μm. Additionally, it is shown that through the proper treatment and evaluation of complementary MA-XRF data, one may overcome some of the fs-LIBS limitations and thoroughly investigate a painting's stratigraphy. Given the micro-invasive character of fs-LIBS and the non-invasive character of MA-XRF, combining the selected analytical methods is a promising tool for painting investigation. [ABSTRACT FROM AUTHOR]

Highly efficient and low-cost materials for the degradation of organic dyes in wastewater remain the focus of environmental protection and water pollution control, in which, nanozymes have been at the forefront for the development of a new platform and aroused more and more attention. In this work, a nanoceria@shaddock peel-derived nanocomposite (Ce@CSP) with excellent peroxidase-like performance in methyl violet (MV) degradation as well as ascorbic acid (AA) detection was synthesized by a simple one step in situ pyrolysis of cerium ammonium nitrate (Ce(NH4)2(NO3)6) and pretreated shaddock peel. By means of the cooperative-reinforcing peroxidase-like activity of the porous carbon material originating from shaddock peel (CSP) and the loaded CeO2 nanoparticle, the obtained nanozyme Ce@CSP displayed a superior catalytic ability in the catalyzed oxidation of the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2. Specifically, a synergetic absorbent property was also demonstrated by the porous carbon material, bringing the target molecules in close proximity to the nanozyme catalyst and therefore enabling effective decoloration of MV and colorimetric detection of AA with a linear range of 1.6–17.3 μM and a detection limit of 1.07 μM. The current work has realized effective decoloration of MV in real water samples and provided a wide range of potential applications of low-cost and eco-friendly materials in organic dye treatment. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) lamellar membranes have attracted a lot of attention as a possible solution for water purification applications. In this work, asparagine amino acid-modified GO-based membranes (As@GO) are prepared with different thicknesses. The as-prepared As@GO-based membranes are used for the separation of organic dyes and heavy metal ions. The 300 nm-thick As@GO multilayer membrane shows high rejection, i.e., 99.8% and 99.9% of methylene blue (MLB) and rhodamine B (RB) dyes, respectively, along with an exceptional water permeability of ∼1740 ± 10 L m−2 h−1 bar−1. Furthermore, the As@GO membrane also demonstrates excellent rejection of up to 95.6% and 96.7% for cadmium (Cd2+) and lead (Pb2+) ions, respectively. These membranes are also highly stable in water for up to 34 days and do not swell. These results suggest the valuable experimental basis for the design and development of stable GO membranes (GOMs) with high permeability and superior separation selectivity for applications in the separation fields of valuable metal ion extraction from seawater and other wastewater purification, etc. [ABSTRACT FROM AUTHOR]

Nitric acid became commonly available in the seventeenth century. Since then, it held the interest of chemists, especially those interested in the art of dyeing. Due to what is now called the xanthoproteic reaction (from Greek xanthós, describing shades of yellow), nitric acid produces a stable yellow colouration in proteinaceous materials, such as wool, silk, and bones. The chemistry of this reaction is well understood today. Less well-known is that it held the interest of dyers in the past. Dyers considered the ability of nitric acid to give a yellow colour to certain substances a solution to giving materials a durable, that is, a lasting, yellow colour. Yellow, indeed, posed a problem in the art of dyeing. Before the discovery of synthetic dyes in the mid-nineteenth century, there were no organic yellow dyes with long-term colour stability. Using historical dyeing manuals and chemistry treatises, combined with our practical engagement with the processes they describe, this paper traces how, between the seventeenth and nineteenth centuries, dyers explored nitric acid while examining the durability of yellow colourations. Based on these explorations into nitric acid, the chemical arts developed theories about the nature of colour, and about the causes for its relative permanence. [ABSTRACT FROM AUTHOR]

The document titled "Photovoltaics literature survey (no. 188)" is a compilation of recently published journal articles that cover a wide range of topics related to photovoltaics. These articles discuss various aspects of solar energy, including the development of efficient solar cells, advancements in perovskite solar cells, the use of quantum dots in solar cells, optimization of photovoltaic systems, the impact of solar energy on the environment and economy, and recycling of solar panels. It is important to note that inclusion in the list does not imply endorsement of the paper's quality. The articles provide valuable insights into the latest research and developments in the field of solar energy. [Extracted from the article]

Among the various anti‐counterfeiting solutions, fluorescent compounds gained attention as challenging to copy solutions because of astute technological improvements. However, fluorescent compound usage in counterfeit detection is limited due to high price of rare earth metals, the low photostability of pigments or organic dyes, and the long‐term toxicity of conventional semiconductor quantum dots. Herein lies the value of carbon dot, a very stable, reasonably priced, and environmentally friendly material with intriguing features. In this work the development of blue fluorescent, N‐doped carbon dots (NCD) from waste bamboo stem cuttings via hydrothermal route is presented as an environmentally friendly approach to reduce the risk of toxic gas evolution from burning of bamboo waste. The carbon dot's practical application in anti‐counterfeit printing was ascertained by comprehending it's superior properties, such as high water solubility, eco‐friendliness, dazzling fluorescence, and surface functionalization through various characterization techniques. Inkjet printing of the designs on paper substrate using the aqueous NCD ink displayed reversible encryption‐decryption ability through variation of pH. The development paves the way for value‐added utilization of waste bamboo cuttings in fluorescent ink production. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks and coordination polymers (MOFs/CPs) have emerged as a rare category of multidimensional materials with applications in many fields, particularly as photocatalysts for aromatic dyes and for the luminescent sensing of volatile organic solvents (VOCs), anions, cations, etc. Herein, a luminescent zinc(II) coordination polymer (ZnCP) was prepared using 3,5-diamino triazole (DAT) and 1,3,5-benzenetricarboxylic acid (BTC) under solvothermal conditions and was fully characterized by FTIR spectroscopy, powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) analysis, and single X-ray crystallography. Moreover, the photocatalytic performance of the ZnCP in decomposing an aqueous solution of methyl green (MG) was examined. Photocatalysis results indicated a 99.61% efficiency in the presence of the ZnCP under visible light. Furthermore, an active species trapping experiment helped deduce a possible photocatalysis mechanism of MG degradation. Interestingly, the ZnCP also acted as a potential luminescent sensor for the detection of cations Fe3+ and Cu2 and anions Cr2O72− and MnO4−, with outstanding limit of detection (LOD) values of 2.44 nM for Fe3+, 3.50 nM for Cu2+, 3.14 nM for Cr2O72−, and 2.54 nM for MnO4−. Thus, the designed luminescent zinc(II) coordination polymer holds the potential to act as a photocatalyst as well as a luminescent sensor. [ABSTRACT FROM AUTHOR]

[Display omitted] • Modified red mud-based materials can remove dyes from wastewater. • Four removal mechanisms of dye from wastewater are reviewed. • Future research of modified RM-based materials for dye removal are pointed out. Red mud (RM) is a highly alkaline solid waste generated during alumina production and should be disposed of and recycled in an environmentally sound manner. Red mud is rich in metal compounds, making it a promising material for environmental remediation treatment. However, there are fewer papers on the removal of organic dyes from wastewater using modified red mud-based materials. Therefore, this paper provides a comprehensive review on the properties of dyes and reveals the adverse effects caused by dye wastewater pollutants. The application of modified red mud-based materials in dye wastewater are further reviewed. Meanwhile, the removal mechanism includes electrostatic gravitational interaction, hydrogen bonding, π-π bonding, and catalytic oxidation. In addition, this paper suggests that the activation methods for red mud materials should be optimized in future studies as well as develops red mud-based materials with absorbing many dyes. This paper aims to expand modified red mud-based materials application for removing organic pullents from wastewater and red mud utilization. [ABSTRACT FROM AUTHOR]

Azo dyes are difficult to degrade, dark in color and toxic in the aqueous environment, which will harm the ecological environment and human health if left untreated. Photocatalytic technology has a wide range of applications in the treatment of printing and dyeing wastewater; in the present study, nano Zr–BiOI/GO photocatalytic composites were prepared by a hydrolysis method using Bi(NO 3) 3 –5H 2 O and ZrOCl–8H 2 O as precursors and GO as carriers. The structure and properties of the samples were characterized by combining test methods such as XRD, FESEM, TEM, XPS, and UV–vis. Congo red (CR) was used as the target pollutant to assess the photocatalytic performance of the prepared materials. The results showed that the specific surface area of 10 % Zr–BiOI/GO increased from 21.98 m2/g to 152.79 m2/g, and the average particle size decreased from 21.61 nm to 17.75 nm compared with that of BiOI. Compared with BiOI, the light-absorption threshold of 10 % Zr–BiOI/GO was increased from 640.6 to 726.4 nm, and the forbidden bandwidth was decreased from 1.94 eV to 1.71 eV. In addition, the nanocomposites exhibited excellent stability and removal of organic dyes and could be used as a potential photocatalyst for water remediation under visible light. The removal of CR by 10 % Zr–BiOI/GO composite was 95.42 % at 120 min. The photocatalytic degradation process of Zr–BiOI/GO conformed to the first-order kinetic model, and the correlation coefficient of the kinetic curve of 10 % Zr–BiOI/GO was 0.9465 and the reaction rate constant was the greatest at 0.0221 min−1. Superoxide radicals [·O 2 −] play a major role in photocatalytic activity. The results indicate that nanocomposites are a promising candidate for photocatalytic degradation of water pollutants. In this paper, Zr–BiOI/GO photocatalytic composites were prepared by a simple hydrolysis method, which possessed higher specific surface area and narrower forbidden bandwidth than pure BiOI, and could remove up to 95.42 % of Congo red (CR) solution under visible light, in addition to the high stability and recycling rate of Zr–BiOI/GO. [Display omitted] • The pore structures of Zr–BiOI/GO photocatalytic materials prepared by hydrolysis method were well developed. • The maximum removal of Congo red by mesoporous Zr–BiOI/GO photocatalytic material was 96.84 %. • Paradigm of Zr–BiOI/GO resource recovery and wastewater treatment was provided. • Long-term experiments were conducted with excellent stability. [ABSTRACT FROM AUTHOR]

The construction of multi-emission center MOFs and its high-dimensional sensing detection of analytes have broad development prospects. This paper focuses on the preparation strategies of MOFs with three or more luminescent centers in recent years, and then discusses the recognition ability of high-dimensional sensing based on multi-luminescent MOFs to target analytes. [Display omitted] • The three-emission sensor has higher selectivity and accuracy. • The three-emission sensor can detect and identify multiple analytes at the same time, which is more suitable for the analysis of real samples. • The color change before and after detection by the three-emission sensor is easier to be recognized by the naked eye. In recent years, multi-dimensional sensing methods based on multi-emission MOFs have attracted great attention from researchers due to their excellent sensitivity and selectivity to the target analytes. Through the mixed ligand strategy or encapsulating the appropriate fluorophores (lanthanide ions, luminescent ligands, metal ligand complexes, organic dyes, carbon dots, etc.) in the MOFs channel, MOF-based proportional sensors with multiple luminescent centers can be successfully designed. In this paper, the research progress of multi-dimensional sensors based on MOFs in recent years is reviewed, with emphasis on the preparation of three-emission MOF composites and their applications in detecting ions, pH, volatile organic compounds and organic molecules. This paper will be of great significance for researchers interested in multi-dimensional sensing based on three-emission MOFs to understand its research progress. [ABSTRACT FROM AUTHOR]

In this paper, we present a new catalyst based on graphene oxide deposited on PES fabric and decorated with Cu0 and Ag0 NPs. The material was created via dip-coating followed by in-situ reduction of Cu2+ and Ag+ to Cu0 and Ag0 on its surface. Different physico-chemical characterizations were performed to investigate the possible interfacial interactions between PES, GO, and metallic ions. The PES-GO/Cu0-Ag0 was evaluated for the reduction of 4-nitrophenol (0.03. 10-3 M), Rhodamine B (20 ppm) and Methyl Orange (20 ppm). The PES-GO/Cu0-Ag0 catalyst shows outstanding catalytic activity for the reduction of all organic compounds tested. The reaction constant for 4-NP, RhB, and MO was 0.564, 0.569, and 0.42 min-1, respectively. Furthermore, the findings indicate that PES-GO/Cu0-Ag0 coatings on PES substrate may be advantageous to avoid problems with powder separation. [Display omitted] [ABSTRACT FROM AUTHOR]

Facile preparation route for cobalt tungstate (CoWO 4) via cost effective, time saving, easy and solution combustion approach is described in the present paper. The structural, morphological properties of cobalt tungstate characterized by different physiochemical techniques which include X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray absorption (EDS). The optical properties assessed by UV–visible spectroscopy (DRS) and photoluminescence spectroscopy (PL). Using these methods, it was discovered that CoWO 4 which has been synthesized displayed a monoclinic phase of Wolframite with great crystallinity and purity. The average crystallite size of prepared CoWO 4 was 22 nm and band gap obtained was 2.84 eV due to which it can be used as visible light photocatalyst in aqueous medium. As a result, in this study, the photocatalytic degradation ability of CoWO 4 was assessed by observing the aqueous phase degradation of the most widely used dyes, methylene blue (MB) and Rhodamine-B as well as Cr(VI) reduction under visible light. Almost all MB degraded in 90 min whereas 69 % degradation of RhB takes place in 240 min under visible light irradation. The different aspects for low rate of photodegradation of RhB dye than MB dye was also discussed in this report. The present study deals advanced approach that CoWO 4 can also be used as capable visible light photocatalyst for degradation of dangerous contaminants and for reduction of carcinogenic Cr(VI) into nontoxic Cr(III) from waste water. [ABSTRACT FROM AUTHOR]

[Display omitted] • BaCu x Ti 1-x O 3-x nanofibers were prepared by hydrothermal method. • Poling can improve the tribocatalytic activity of BaCu 0.02 Ti 0.98 O 2.98 nanofibers. • High conductivity is resulted from Cu2+ doping, smaller grain size and poling effect. BaCu x Ti 1-x O 3-x (x = 0, 0.01, 0.02, 0.03, 0.04) nanofibers were synthesized via the hydrothermal method and subsequently subjected to poling. The impact of composition on their tribocatalytic performance and the underlying catalytic mechanism were investigated. After 100 min, all poled BaCu x Ti 1-x O 3-x nanofibers exhibited superior tribocatalytic efficiency compared to pure BaTiO 3 , with BaCu 0.02 Ti 0.98 O 2.98 poled nanofibers achieving a degradation rate of up to 80 % for RhB solution. This is because the increased conductivity and reduced carrier recombination rate which were caused by a 0.02 Cu doping, smaller grain size and poling effect. Control experiments confirmed that both stirring and the presence of a catalyst are essential prerequisites for tribocatalysis. Furthermore, the universality, selectivity, stability, and main active group O 2 – of poled BaCu x Ti 1-x O 3-x (x = 0, 0.01, 0.02, 0.03, 0.04) nanofibers were verified. Lastly, although the tribocatalytic efficiency presented in this paper does not match that of piezoelectric catalysis, the latter requires ultrasonic conditions that are challenging to find naturally. As a result, tribocatalysis offers greater potential for practical applications. [ABSTRACT FROM AUTHOR]

Two novel Zinc-porphyrin central dyes (T-5 and T-6) containing acetylene moiety have been designed and synthesized for application in dye-sensitized solar cells (DSSCs). The light-harvesting capabilities and photovoltaic performance of these dyes were investigated systematically through comparison of different donor (D) unit. Devices fabricated from phenoxazine (POZ)-based molecule T-5 showed higher short-circuit current (J SC , 11.32 mA cm-2) compared to T-6 which based on phenothiazine (PTZ) (10.1 mA cm-2) under standard global AM 1.5 G solar condition. This is due to the fact that the POZ unit has a greater electron supply capacity than the PTZ unit. The introduction of the acetylene moieties into the molecular structure broadens the light absorption range of the dye molecule to the entire visible range and the near-ultraviolet region. The conclusions of this paper demonstrate that incorporating strong electron donor groups in dye molecules, in synergy with conjugated groups, broadens the spectral range of light absorption, thereby enhancing the performance of the dye device. [Display omitted] • Designed, synthesized and compared two novel zinc-porphyrin organic dyes T-5 and T-6 with D-A-π-A structure containing the acetylene groups. • The novel dye T-5 has a higher molar extinction coefficient, which expands its absorbance range into the near-ultraviolet region. • Theoretical calculations were used to corroborate the performance differences obtained experimentally. [ABSTRACT FROM AUTHOR]

• Cost-effective green synthesis process of β-CoMoO4 materials. • The good absorption in the visible range, as revealed by investigations of the optical properties, makes this material a suitable photocatalyst for degrading organic dyes. • High stability and photo-degradation efficiency, thanks to the nanowire structure of cobalt-molybdate material. This paper presents a simple and low-cost one-step synthesis method of cobalt molybdates. Several structural, optical and catalytic characterization techniques are used in synergy to highlight the properties of the synthesized material. EDX, FTIR, and X-ray diffraction analysis confirmed the formation of the pure β-CoMoO 4 phase. The obtained β-CoMoO 4 particles are polydisperse with quasi-agglomerated nanowires shape and the diameters are estimated in the range (115 ± 22) nm by atomic force microscopy (AFM). In addition, the band gap energy, E g = 2.81 eV, shows that β-CoMoO 4 nanowires can absorb in the near-UV visible range and therefore act as a photocatalyst. A photocatalytic activity against methylene blue (MB) degradation of up to 52 % was observed under visible light irradiation. As a result, a pseudo-first-order kinetic rate constant of MB photodegradation, in the presence of β-CoMoO 4 nanowires, was estimated to be 0.013 min−1. The photodegradation efficiency of the synthesized material could be mainly related to the positions of the conduction (E CB = 0.23 eV) and valence (E VB = 3.04 eV) potential energies, which are favorable to the generation of reactive oxygen species (ROS). Moreover, the sample was recovered from the solution by a simple centrifugation and reused three times without significant loss in photocatalytic activity. We experimentally prove that the synthesized nanowires show strong photodegradation efficiency and photocatalytic stability for three consecutive cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two organic fluorescent dyes DCM-1 and DCM-2 with near-infrared fluorescence were designed and synthesized. • DCM-1 and DCM-2 have a specific fluorescence response to viscosity. • DCM-1 and DCM-2 can be successfully applied to the imaging of dynamic changes in viscosity in living cells. The development of near-infrared organic fluorescent dyes with tunable emission profiles is highly required in the field of biological sensing and imaging. In this paper, we designed and synthesized two organic fluorescent dyes, DCM-1 and DCM-2, through the hybridization of indolizine and dicyanomethylene-4H-pyran skeleton. These two compounds show near-infrared fluorescence with emission maximum approximately at 640 and 680 nm, respectively. Notably, both DCM-1 and DCM-2 have specific responses to viscosity without being interfered by biological relevant species. Cell experiments demonstrate that DCM-1 and DCM-2 can detect dynamic changes in viscosity within living cells, suggesting their potential applications in chemical biology research. [ABSTRACT FROM AUTHOR]

Boron-doped diamond (BDD) deposited on a titanium (Ti) metal substrate has great potential for electrocatalytic degradation of organic pollutants; however, poor adhesion between BDD and Ti hinders stability. In this paper, we report the controllable synthesis of a polycrystalline BDD/boron-doped graphene (BG) film on Ti mesh with a diameter of 60 mm. The BG interlayer enhanced the surface adhesion between BDD and the Ti substrate and promoted the (111)-oriented growth of BDD crystals. Because the BG layer also serves as a fast electron transport layer, the optimized BDD/BG/Ti electrode has a highly effective electroactive area and a low liquid-solid interface resistance, which are respectively 1.9 times greater and 1/2 of those of the BDD/Ti electrode. An electrocatalytic system with an optimized BDD/BG/Ti mesh as the anode and a vertical BG/Ti mesh as the cathode degraded 15 mg L−1 of methyl orange (MO) at a voltage of 5 V, with a fading time of 60 s. Furthermore, the MO degradation efficiency using the BDD/BG/Ti mesh anode was 93.43 %, approximately 10.24 % higher than that of the BDD/Ti mesh anode. The BDD/BG structure provides a novel route for designing highly electrocatalytic BDD electrodes with large dimensions. Furthermore, the arrays of BDD/BG and vertical BG mesh electrodes rapidly degraded organic dyes, such as MO, methylene blue, methylene green, rhodamine B, basic fuchsine, and methyl green thus can be applied for the electrocatalytic degradation of high-salt dye wastewater without reagents. [Display omitted] • Boron-doped diamond (BDD)/boron-doped graphene (BG)/Ti mesh electrodes were prepared. • Interlayer BG promotes the growth of (111)-oriented polycrystalline BDD films. • BDD/BG/Ti mesh electrode has high electrocatalytic activity and stability. • BDD/BG anodes rapidly degrade organic dyes electrochemically. • New strategy for the rapid degradation of high-salt dyes without reagents was proposed. [ABSTRACT FROM AUTHOR]

The ever-increasing expansion of chemical industries produces a variety of common pollutants, including colors, which become a global and environmental problem. Using a nanocatalyst is one of the effective ways to reduce these organic contaminants. With this in mind, a straightforward and effective method for the production of a novel nanocatalyst based on lignin-derived carbon, titanium dioxide nanoparticles, and Ag particles (TiO2/C/Ag) is described. The preparation of carbon and Ag particles (in sub-micro and nano size) was carried out by laser ablation in air. The nanocomposite was synthesized using a facile magnetic stirrer of TiO2, C, and Ag. According to characterization methods, a carbon nanostructure was successfully synthesized through the laser irradiation of lignin. According to scanning electron microscope images, spherical Ag particles were agglomerated over the nanocomposite. The catalytic activities of the TiO2/C/Ag nanocomposite were tested for the decolorization of methylene blue (MB) and Congo red (CR), employing NaBH4 in a water-based solution at 25 °C. After adding fresh NaBH4 to the mixture of nanocomposite and dyes, both UV absorption peaks of MB and CR completely disappeared after 10 s and 4 min, respectively. The catalytic activity of the TiO2/C/Ag nanocomposite was also examined for the reduction of 4-nitrophenol (4-NP) using a NaBH4 reducing agent, suggesting the complete reduction of 4-NP to 4-aminophenol (4-AP) after 2.30 min. This shows excellent catalytic behavior of the prepared nanocomposite in the reduction of organic pollutants. [ABSTRACT FROM AUTHOR]